IgA Pemphigus

• Figure 3.26 A: Bullous pemphigoid (Courtesy of Dr. Paul Getz) B: Bullous pemphigoid (Courtesy of Dr. Iris K. Aronson) C: Bullous pemphigoid (Courtesy of Dr. Iris K. Aronson)

  Blistering disease with intraepidermal IgA deposits
• Autoantigen : desmocollin 1 (SPD), ± desmoglein 1/3 (IEN)
• Clinical : two types
  • Subcorneal pustular dermatosis (SPD): serpiginous vesicles or pustules; may be associated with underlying IgA gammopathy
  • Intraepidermal neutrophilic type (IEN): flaccid pustules and bullae involving intertriginous locations which enlarge forming annular or polycyclic (sunflower-like) arrangement
• Histology: intraepidermal pustule or vesicles containing neutrophils, no acantholysis
• DIF : intercellular IgA deposition (unlike SCPD of Sneddon-Wilkinson)
• IIF : + in 50%, intercellular IgA
• Treatment : dapsone, oral corticosteroid